CPU usage higher than what shows in Task Manager

Salvation!

I am writing this post because I am desperate. I searched the internet back to back and found some solutions to the problem in the title, but they didn’t work for me. These included upgrading drivers (I upgraded them all), scanning your computer for viruses (done with 3 different programs, nothing, I also checked my users and nothing new there appeared), checking resource monitor for strange programs that are using my CPU (shows the same as task manager), cleaning up the inside of my PC (done, a slight improvement but not as much as it should) and, of course, restart the computer. I don’t want to spend money on a format just yet, I want to make sure what it is first.

The CPU in question: an i7-4790K over 7 years old. I have never overclocked it.

So, for the problem to solve: the CPU total is many greater than the separate tasks it performs. I’ve seen people online telling others that 0.1% or 0% tasks add up to that. It’s literally impossible. I can run my CPU at 60% in a game, then when I look in task manager it’s at 98% utilization. The attached screenshot is from when the game was minimized. I only noticed this issue because some games were dropping to 18 FPS and I was looking into what was causing it.

Is this a system issue and I need a format or is it just a case of my CPU aging? Has anyone else ever had such a problem?

https://imgur.com/a/Br9tlDW